[RFC][PATCH 1/12] PM: Add flag for devices capable of generating run-time wake-up events

Rafael J. Wysocki
2009-11-29T15:45:52Z

From: Rafael J. Wysocki <rjw@sisk.pl>

Apparently, there are devices that can wake up the system from sleep
states and yet are incapable of generating wake-up events at run
time. Thus, introduce a flag indicating if given device is capable
of generating run-time wake-up events.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
Documentation/power/runtime_pm.txt | 7 +++++--
include/linux/pm.h | 8 +++++---
include/linux/pm_runtime.h | 12 ++++++++++++
3 files changed, 22 insertions(+), 5 deletions(-)

Index: linux-2.6/include/linux/pm.h
===================================================================
--- linux-2.6.orig/include/linux/pm.h
+++ linux-2.6/include/linux/pm.h
@@ -179,9 +179,10 @@ typedef struct pm_message {
* This need not mean that the device should be put into a low power state.
* For example, if the device is behind a link which is about to be turned
* off, the device may remain at full power. If the device does go to low
- * power and if device_may_wakeup(dev) is true, remote wake-up (i.e., a
- * hardware mechanism allowing the device to request a change of its power
- * state, such as PCI PME) should be enabled for it.
+ * power and is capable of generating run-time wake-up events, remote
+ * wake-up (i.e., a hardware mechanism allowing the device to request a
+ * change of its power state via a wake-up event, such as PCI PME) should
+ * be enabled for it.
*
* @runtime_resume: Put the device into the fully active state in response to a
* wake-up event generated by hardware or at the request of software. If
@@ -434,6 +435,7 @@ struct dev_pm_info {
unsigned int idle_notification:1;
unsigned int request_pending:1;
unsigned int deferred_resume:1;
+ unsigned int run_wake:1;
enum rpm_request request;
enum rpm_status runtime_status;
int runtime_error;
Index: linux-2.6/Documentation/power/runtime_pm.txt
===================================================================
--- linux-2.6.orig/Documentation/power/runtime_pm.txt
+++ linux-2.6/Documentation/power/runtime_pm.txt
@@ -71,9 +71,9 @@ what to do to handle the device).
purpose).

In particular, if the driver requires remote wakeup capability for proper
-functioning and device_may_wakeup() returns 'false' for the device, then
+functioning and device_run_wake() returns 'false' for the device, then
->runtime_suspend() should return -EBUSY. On the other hand, if
-device_may_wakeup() returns 'true' for the device and the device is put
+device_run_wake() returns 'true' for the device and the device is put
into a low power state during the execution of its bus type's
->runtime_suspend(), it is expected that remote wake-up (i.e. hardware mechanism
allowing the device to request a change of its power state, such as PCI PME)
@@ -214,6 +214,9 @@ defined in include/linux/pm.h:
being executed for that device and it is not practical to wait for the
suspend to complete; means "start a resume as soon as you've suspended"

+ unsigned int run_wake;
+ - set if the device is capable of generating run-time wake-up events
+
enum rpm_status runtime_status;
- the run-time PM status of the device; this field's initial value is
RPM_SUSPENDED, which means that each device is initially regarded by the
Index: linux-2.6/include/linux/pm_runtime.h
===================================================================
--- linux-2.6.orig/include/linux/pm_runtime.h
+++ linux-2.6/include/linux/pm_runtime.h
@@ -50,6 +50,16 @@ static inline void pm_runtime_put_noidle
atomic_add_unless(&dev->power.usage_count, -1, 0);
}

+static inline bool device_run_wake(struct device *dev)
+{
+ return dev->power.run_wake;
+}
+
+static inline void device_set_run_wake(struct device *dev, bool enable)
+{
+ dev->power.run_wake = enable;
+}
+
#else /* !CONFIG_PM_RUNTIME */

static inline int pm_runtime_idle(struct device *dev) { return -ENOSYS; }
@@ -73,6 +83,8 @@ static inline bool pm_children_suspended
static inline void pm_suspend_ignore_children(struct device *dev, bool en) {}
static inline void pm_runtime_get_noresume(struct device *dev) {}
static inline void pm_runtime_put_noidle(struct device *dev) {}
+static inline bool device_run_wake(struct device *dev) { return false; }
+static inline void device_set_run_wake(struct device *dev, bool enable) {}

#endif /* !CONFIG_PM_RUNTIME */